Electronic equipment such as televisions, telephones, radios, and computers are often constructed using semiconductor components, such as integrated circuits, memory chips, and the like. The semiconductor components are typically constructed from various microelectronic devices fabricated on a semiconductor substrate, such as transistors, capacitors, diodes, resistors, and the like. Each microelectronic device is typically a pattern of conductor, semiconductor, and insulator regions formed on the semiconductor substrate.
The density of the microelectronic devices on the semiconductor substrate may be increased by decreasing the size, or linewidth, of the various semiconductor devices. The decrease in linewidth allows a larger number of such microelectronic devices to be formed on the semiconductor substrate. As a result, the computing power and speed of the semiconductor component may be greatly improved.
In order to decrease the linewidth of the microelectronic device, the size and thickness of the conductor, semiconductor, and insulator regions forming each microelectronic device must be reduced. As the size of the microelectronic device is scaled down to sub-micron sizes, there is a need to form shallow doped regions in the semiconductor substrate. For example, a shallow doped region may be used to construct a shallow junction transistor. Shallow junction transistors are less susceptible to current leakage and the formation of unwanted parasitic connections and devices.
Some techniques for fabricating a shallow doped region include the use of an ion beam to shallowly implant a dopant into the semiconductor substrate. As is well known to those in the art, the ion implantation process generally operates by ionizing and accelerating dopant atoms into the semiconductor substrate. The dopant atoms are thereby implanted into the semiconductor substrate. The doped region of the semiconductor substrate generally forms a conductive region, such as a source or drain component of a transistor.
The ion implantation process often damages the crystal lattice of the semiconductor substrate being implanted. In the case of shallow doped regions, ion implantation damage generally has a greater adverse affect because the size of the doped region is small. For example, damage to the source and drain regions of a shallow junction transistor may result in an increase in the leakage and in the threshold voltage of the transistor, thereby decreasing the performance of the transistor.